Prevalence of bulimia was estimated from a cross-sectional general population survey of 1498 adults, using the Diagnostic Interview Schedule (DIS) administered by trained lay interviewers. Lifetime prevalence of the DSM-III syndrome in adults aged 18–64 was 1·0% and this was concentrated in young women: in women aged 18–44 lifetime prevalence was 2·6%, and 1·0% currently had the disorder. Based on clinicians' reinterviews of random respondents and identified and marginal cases, the prevalence of current disorder using criteria for draft DSM-III-R bulimia was 0·5%, for DSM-III it was 0·2%, and for Russell's Criteria bulimia nervosa 0·0%. A strong cohort effect was found, with higher lifetime prevalence among younger women, which is consistent with a growing incidence of the disorder among young women in recent years. Although elements of the syndromes were so common as to suggest that dysfunctional attitudes to eating and disturbed behaviour surrounding eating are widespread, there was little evidence of the bulimia syndrome having become an epidemic on the scale suggested by early reports.